1. Field of the Invention
The present invention relates to the improvement of a device for absorbing the torsional vibration from a drive train of a vehicle.
More specifically, the present invention is directed to a compression spring assembly, having a roller member thereon, in combination with a drive plate in which the compression spring assembly and roller member interact with the drive plate to absorb torsional vibration from the drive train of a vehicle. A rolling friction damping device is thus achieved in which an optimum hysteresis for a damping effect is obtained.
2. Description of Related Art
Generally, in an engine, the expansion stroke is only an output stroke and a suction stroke. A compression stroke and an exhaust stroke are output stroke reduced. In an expansion stroke, a turning effect of a drive plate is increased and/or decreased, so an engine speed varies periodically. The known flywheel is manufactured in order to prevent the above mentioned periodic variance factor of the engine speed.
Namely, the inertial force of the conventional flywheel is used to change the fluctuating rotating force of the drive plate.
The present invention utilizes the effects of the drive plate and provides and/or utilizes the characteristic shape thereof in the present invention. Specifically, when turning a damper of a dual mass vibration damping flywheel for vehicles, the optimum vibration damping effect can be achieved by realizing a hysteresis thereof. It is the inventors"" discovery that an ideal torque curve was needed to achieve the shock absorbing effect of the dual mass flywheel. This can be obtained by controlling a drive plate""s function in accordance with the engine characteristic and/or traveling condition of the vehicle.
Accordingly, it is an object of the invention to provide a dual mass flywheel which absorbs torsional vibration from a drive train of a vehicle.
It is another object of the invention to provide a dual mass flywheel in which a drive plate thereof has a characteristic shape.
It is yet another object of the invention to provide a dual mass flywheel in which the characteristic shape of the drive plate interacts with a compression spring assembly.
It is still another object of the invention to provide a dual mass flywheel in which the compression spring assembly includes a roller on at least one end thereof, the roller following the characteristic shape of the drive plate.
It is a further object of the invention to provide a dual mass flywheel for absorbing torsional vibration from a drive train of a vehicle which is easy to manufacture and simple to use.
These and other objects of the invention are achieved by providing a dual mass vibration damping flywheel including a primary mass flywheel and a secondary mass flywheel connected to the primary mass flywheel. A drive plate having a characteristic shape is positioned between the primary mass flywheel and the secondary mass flywheel, the drive plate being rotated in response to rotation of the primary mass flywheel. A spring assembly is provided having a roller member at one end thereof, the roller member being in contact with the characteristic shape of the drive plate and compressing the spring assembly upon rotation of the drive plate. The drive plate is formed as an axe shape such that the roller of the spring assembly rolls in contact with the characteristic shape of the drive plate upon rotation of the drive plate and the primary mass flywheel. The effect of the spring assembly and roller against the characteristic shape of the drive plate is to dampen the vibration of the dual mass flywheel.